demonpixel

iTrader: (19)

Building a 98 LS1, and I've got a set of Yella Terra Ultra Lites 1.7 ratio. The instruction manual claims that this is a direct stock replacement. I'm following these instructions: http://www.ls1howto.com/index.php?article=21

I've got both pushrods on the #1 cylinder down, with the pushrods on the base of the lobe. I set the preload just fine on the first rocker pair.

On the second, I put the stock bolt through the left rocker, and it went in just fine. Then I put another stock bolt through the right rocker, and this is how far it went:



I thought ok maybe it's just a really tight fit, I'll just force the bolt through by twisting it with the socket wrench. It was extremely tight, but went through. HOWEVER, I took the bolt out of that tight fitting rocker, and the bolt now looks polished:



Some of the rockers that are left have the bolts fitting into them just fine with no problems. The other rockers have the really really tight fitting.

Has ANYONE encountered this problem? I am in bad need of some advice; what should I do? Is it ok to have those bolts be a very tight fit in these Yella Terras?

Thanks to anyone willing to help

One more q...I'm using an 8 mm socket on these rocker bolts. The ls1howto instructions say that to use a 10mm socket. Do I not have stock bolts or is that a typo???

618HAWK

iTrader: (361)

Did you not get the new set of bolts with your kit. Last kit I installed it came with new bolts just for this reason. Read some where about a interferance problem with the stock bolts.

demonpixel

iTrader: (19)

Thanks for the response Hawk! No, my rockers came with the pedestals and the washers. NO BOLTS AT ALL.

Anyone know where I can get these Yella Terra bolts? I looked on Summit and found nothing.

Also, the interference problem is intermittent. Some of my stock bolts go right through while others don't.

618HAWK

iTrader: (361)

What is the kit pn?
Was it a new complete kit. Like I said the last 2 kits I installed had rockers, pedistals, shims and bolts.

Here see if this will shed some light, or at least a contact.

http://www.yellaterra.com.au/product...goryIdentity=4

supergt99

iTrader: (1)

mine came with bolts also. i would be making some calls right now, they are missing.

01ssreda4

iTrader: (96)

the tight ones i would just hit with some light sandpaper. they will eventually slide through. sounds like slight manufacturing tolerance problems with the bolts.

demonpixel

iTrader: (19)

I was thinking that also red. Those bolts are just to hold the rockers in place so when they are torqued down properly it shouldn't go anywhere right??

Really wanted to get them done this weekend. I got them from my engine shop (a sponsor here) so I guess I can ask them first thing Monday where the bolts are?

The number in the box says 6645, I'm assuming that is the pn.

MrElectric03

iTrader: (71)

Mine came with bolts...will the rocker hit the head of the stock bolts? I seem to remember looking at mine when I installed them and noticed that the rocker would contact the head of the stock bolt.

demonpixel

iTrader: (19)

Hmm not sure what you mean...on some of the rockers the head of the bolts makes contact, yes.

demonpixel

iTrader: (19)

Looked at the Yella Terra instructions one more time. Definitely looks like allen head bolts in the little diagrams.

Does anyone know the specs on this Allen head bolt? Maybe I can just bring the rockers to Ace Hardware and pick some Grade 8s that fit?

Futher thoughts/suggestions?

TappetHead

Hi Zig.
Sounds like either a packing error or you have got an older set that have been sitting on someone’s shelf for a few months.
We used to recommend re-using the original bolts but found problems (like you are experiencing) with inconsistent shank diameter and so added a set of socket head cap screws to the set.
I have CC’d Doug Smith at our MS warehouse who has bolt sets in stock.
If you can let him know your delivery address he will send you a set ASAP.
Regards.
Mark (Yella Terra)

Big Bird WS6

iTrader: (9)

my came with bolts. worked great

Coreyc619

as far as will they work if torqued correctly.. with all that interference they wont be torqued correctly. the drag will create a false torque reading hence the reason for thorougly cleaning threads (both sides male and female) and lubing threads before torquing the important stuff like heads/rods/mains etc.

in your case it prolly wont matter but i have no idea how tight those bolts are without holding them in my hands. prolly ok but i wouldnt do it

demonpixel

iTrader: (19)

Good point Corey I thought about that too. I ended up holding off and LME hooked me up with the proper bolts. Can't wait to install these!!

njc.corp

good stuff-its not meant to be that tight-

so good on u for stopping and asking-

i have only heard of u and a other have this issue-

it was a packing error-

Thanks--

demonpixel

iTrader: (19)

Thanks for that man. You have no idea how hard it is to not just want to keep going or take "shortcuts" just to get the install done!!

Building an engine has tested my patience more than all my ex girlfriends put together!!!

Rob@ChampionMotors

Had same problem. Got another set of ls1 bolt and they fit. I guess GM made some tighter than others.